Fundamental study for quantitative evaluation method of skin photo-aging with photoacoustic imaging

Abstract

Photo-aging caused by ultraviolet not only accelerates aging of the skin, but also predisposes to skin cancer precursor symptoms. To evaluate photo-aging, various modalities are being used, such as histopathological diagnosis, optical coherence tomography, ultrasound examination (B-mode imaging). However, they have disadvantages in terms of invasiveness, penetration depth and tissue specificity, respectively. To overcome these defects, photoacoustic imaging (PAI), a novel modality, was used in this work. This modality can portray differences of tissue characteristics non-invasively. To verify the feasibility of quantitative skin aging evaluation with photoacoustic technique, signals from sectioned human skin (cheek and buttock; females from 28 to 95 years old) were measured with photoacoustic microscopy. The effects of photo-aging progress on the signal intensity were investigated. The results demonstrated that the PA signal from the dermis increases with aging progress. These analyses demonstrate the feasibility of quantitative skin aging evaluation with a PA imaging system.